In Java how to turn a String into a char or a char into a String?

In Java, you can easily convert a char to a String and vice versa using the following methods:

Convert a char to a String:
You can convert a single char into a String by concatenating it with an empty string or by using the Character.toString(char) method:
```
char myChar = 'A'; String myString = String.valueOf(myChar); // Using String.valueOf() String anotherString = Character.toString(myChar); // Using Character.toString() 
```
Both of the above approaches will create a String containing the character 'A'.
Convert a String to a char:
You can convert the first character of a String into a char using the charAt(0) method:
```
String myString = "Hello"; char myChar = myString.charAt(0); // Gets the first character 'H' 
```
Keep in mind that this method extracts the character at the specified index (in this case, the first character at index 0). If the String is empty, this will result in an IndexOutOfBoundsException. So, make sure to check the length of the String before converting it to a char if needed.

These methods allow you to convert between char and String types in Java easily.